Gaming computers are some of the most powerful consumer PCs on the market. Though beefy dual-processor workstations exist, they’re for work rather than play. People who buy a powerful computer for personal use usually do it so they can play the latest games.
These computers are impressive, but they also draw a lot of power. This can slightly increase your power bills. More importantly, it often has an impact on the noise and heat your PC puts you. A computer that needs less power for the same task can also perform it while cooler and quieter. But what do you need to ensure efficiency?
The Video Card
Of all the components in a gaming computer the video card consumes the most power. A high-end card can add over 100 watts of power draw to your system when it’s running at full load. Depending on your computer, this could double power demand and drastically increase both noise and heat.
If you’re interested in energy efficiency you should make sure to buy only the quickest video card that you need to obtain a framerate you consider acceptable. A card that is overkill for a particular game will usually use more energy than one which is just adequate, but you likely won’t notice a difference in the game experience. Anandtech’s GPU Bench is a good way of gauging what video card will work for you.
You also need to pay attention to reviews. Some video cards are drastically more efficient than others when performing the same task. NVIDIA’s new video cards based on the Kepler architecture, for example, have remarkably low power draw.
The only way to reduce the power of a card you already have is to underclock it. This is the opposite of overclocking – the clock speed is set below stock rather than above it. This can be accomplished using a tool such as RivaTuner (for NVIDIA products) or settings built in to the card’s driver software (for AMD products).
Your computer’s processor is the second most important contributor to overall power draw. Anyone interested in energy efficiency should simply buy the most powerful Intel processor they can afford. All of Intel’s products beat the snot out of AMD’s efficiency.
What about dual-core vs. quad-core? Dual-cores undoubtedly use less power. Most tests suggest that a Core i3 dual-core processor will use about 20 watts less at load than an entry-level Core i5 quad-core. With that said, a quad-core is much better for serious gamers. It’s worth the extra power.
Don’t plan on overclocking if efficiency is your goal. Processors draw more power as their clock speeds are increased above stock. On the other hand, you can undervolt your processor to reduce its power draw while maintaining the same performance or underclock it to reduce both power draw and performance. This will only be possible if your computer’s BIOS offers configuration options that let you change processor voltage.
The Power Supply
A computer’s power supply is an important factor in overall efficiency. Power supplies are responsible for converting power from a wall socket into usable power for a computer. This process is not 100% efficient. A poor quality power supply can lose 30% of power drawn as heat. That increases overall power draw from the wall socket.
The 80 Plus standard has been created to judge the efficiency of power supplies. Any unit that reaches this standard is at least 80% efficient at all levels of load. There are other even better versions of 80 Plus which are explained in our power supply guide.
An efficient power supply will reduce overall power draw and heat output. It’s also likely to be quieter since it needs less cooling. A handful of supplies, such as the Seasonic SS-460FL, are so efficient they don’t need any fan at all.
Some games offer a maximum framerate setting. This is an excellent way to reduce energy draw when playing a game that is not at all demanding for your video card. Diablo 3, for example, has framerate cap settings that are handy because the game can run at hundreds of frames per second on many gaming PCs.
You might also be able to reduce power draw by enabling V-Sync. This feature caps framerate at a certain maximum to ensure that no frame tearing occurs. In some games, depending on how the feature is implemented, it can reduce power draw by preventing your video card from rendering more frames than required to provide a playable experience.
Reducing video quality is also an option, of course, though it has the obvious trade-off of making your games appear less attractive. I think most gamers are unlikely to find that an acceptable compromise. It also may not impact power draw positively if the game offers no way of limiting framerates.
Gaming will always require more power than most other tasks a computer can perform. This is because a modern game usually places heavy demand on both the processor and the video card. There are not many other applications that do the same.
Still, you can improve your efficiency significantly by taking the suggestions in this article to heart. A gaming rig build with power use in mind can easily be 25% more efficient than one which was built without concern for the same. That will save you money, reduce heat and decrease noise.